Locking mechanism for foldable sofa bed



`June 7, 1960 R. cooPERsMlTH 2,939,155

LOCKING MECHANISM FOR FOLDABLE SOFA BED June 7, 1960 R. cooPERsMlTHLOCKING MECHANISM FOR FOLDABU: som BED Filed April 12, 1957 3Sheets-Sheet 2 June 7, 1950 R. cooPERsMlTi-l 2,939,155

LOCKING MECHANISM FOR FOLDABLE SOFA BED Filed April 12, 1957 ssheets-sheet s 2, www #1M- United States Patent O LOCKING MECHANISM FORFOLDABLE SOFA BED Rudolph Coopersmith, 7574 York Ave., Clayton, Mo.

Filed Apr. 12, 1957, Ser. No. 652,498

4 Claims. (Cl. 5-13) This invention relates generally to foldable sofabed constructions, and more particularly to mechanisms for locking bedframe sections in folded relationship.

An object of the present invention is to provide an improved sofa bedhaving a foldable bed frame and locking means for releasably locking theframe in folded position.

Another object is to provide combination locking means for assuring theproper folding of the bed frame sections and for releasably securing theframe sections in that folded relationship.

Another object is to provide a bed frame adapted to be folded with amattress thereon and having distinct, but cooperative, locking means oneof which locks a pair of bed frame sections in folded position and theother of which locks the folded pair of bed frame sections to a thirdbed frame section during folding movement of the three sections intoseat-forming position in the sofa frame.

These and other objects and advantages will become apparent hereinafter.

Briefly, the invention is embodied in a sofa bed including anarticulated foldable bed frame having first and second sections adaptedto be folded into substantially parallel seat-forming relationship,support means carried by one of the sections and adapted to extend inbracing position from the one section into contact with the other of thesections when the sections are in folded relationship, a folding leverfor moving the support into bracing position relative to the onesection, gravity locking means adapted to engage the folding lever tomaintain the support in bracing position, and other locking meansadapted to lock the support in contacting position on the other sectionduring folding movement of the bed frame sections into seat-formingposition in the sofa frame.

The invention also consists in the parts and in the combinations andarrangements of parts hereinafter described and claimed. In theaccompanying drawings which form a portion of this specification andwherein like numerals refer to like parts wherever they occur:

Fig. 1 isga side elevational view of a sofa bed assembly embodying thepresent invention with the bed frame in unfolded position for use as abed,

Fig. 2 is a fragmentary top plan view showing the unyfolded sofa bedwith the mattress removed,

Fig. 3 is a side elevational View showing in broken lines the bed framemembers in the position of the first fold, and in full lines in a moreadvanced folded position of the bed frame members,

Fig. 4 is a view similar to that in Fig. 3, but showing the bed framemembers in the position of the second full fold,

Fig. 5 is -a view similar to that of Fig. 3, but showing the bed framemembers when the bed is about fully folded within the sofa frame,

2,939,155 Patented June 7, 1960 ing the bed frame members in fullyfolded position in the sofa frame, and

Fig. 7 is a fragmentary perspective view of the bed frame members infully folded position.

Referring now to the drawings in detail, it will be seen that thepresent embodiment of the invention has been illustrated in connectionwith a sofa bed 10 having a sofa frame 11 and a bed frame 12, the latterbeing foldable into the former to provide a seat cushion support andbeing unfoldable therefrom to form a bed structure on which a mattress13 is supported.

The sofa frame 11 includes a side or arm structure 14, a base structure15 supported by legs 16, and a back structure 17. The base structureincludes a front upholstery board 18 with which a movable upholsteryboard 19 mounted on the bed frame 12 is adapted to cooperate when thebed frame is folded into the sofa frame 11.

The foldable bed frame 12 includes a plurality of articulated framesections 23, 24, 25 and 26 that are hingedly connected (Fig. 2) at theiradjacent ends by pins 27, V28 and 29. The foot section 23 has sidepieces interconnected by a transverse or cross bar 30 (Figs. 2 and 7),and the head section 26 also has side pieces connected by a cross bar31. A suitable mattress supporting fabric 32 is mounted on the severalframe sections by a plurality of springs 33.

Inasmuch as the structure for supporting and folding the bed frame 12into the sofa frame 11 is identical on both sides-of the frame, thefollowing description will refer to only one side. A supporting leg 34is provided for the bed frame 12 at the outer end of the foot or firstsection 23 and an intermediate supporting leg 35 is provided for thebody or second section 25. These supporting legs 34 and 3S are pivotedto the frame sections 23 and 25, respectively, by pins 36 and 37, andmeans are provided for folding the legs when the bed frame 12 is foldedinto the sofa frame 11. The intermediate or third section 24interconnects and is supported by the rst and second sections 23 and 25,and the head or fourth section 26 is pivotally connected by an arm 38 toa brace 39 secured to the base structure 15 of the sofa frame 11.

As shown in Fig. l, when the foldable bed frame 12 is Vin extended orbed forming position, the frame sections are horizontally coplanar andthe sections 23 and 25 are supported by the legs 34 and 35,respectively. In folding the bed frame 12 into the sofa frame 11, therst section 23 is raised into vertical position (as shown in brokenlines in Fig. 3) and folded over or pushed inwardly and downwardly intoa horizontal position in spaced parallel relation with the secondsection 25 (Fig. 4). This latter folding action brings the third section24 into a vertical position substantially perpendicular to -both thelirst and second sections 23 and 25. The folded first, second and thirdsections are then rocked downwardly and inwardly (Figs. 5 and 6) intoseat-forming position, the fourth section 26 pivoting into a verticalposition adjacent to the back structure 17 of the sofa frame 11.

The linkage or lever means for controlling the folding of vthe bed frame12 into the sofa frame 11 includes a bell crank 42 having a short leg 43and a long leg 44, the bell crank 42 being pivotally connected to thesecond section 25 by a pin 45. The end of the short leg 43 is pivotallyconnected by a pin 46 to one end of a link 47, the other end of which ispivotally connected to the intermediate bed frame supporting leg 35 by apin 48. The end of the long leg 44 of the bell crank 42 isv pivotally tconnected by a link 49 to the sofa frame 11, and a lever 'Figf 6 isanother view similar to that of Fig. 3 showbar 50 has one end pivotallyconnected to the long leg 44inwardly .of its end .by;a .pin 51. Theother end of the lever bar 50 is pivotally connected by a pin 52 toanother brace 53 or thelike secured to the base structure A15 of thesofa frame 11. kThe link 49 and lever bar 50 coact 'to control theclockwise folding action of the bell crank 42 to cause the bed frame 12to rock into seatforming position in the sofa frame 1-1, as shown'in`Figs. 4, 5 and 6. As the bell crank 42 is turning in a clockwisedirection to fold the bed frame 12 -intorthe sofa frame 11, the link 47connected to the supporting leg 35 Vis Vturning in a counterclockwisedirection to fold they leg 35 aboutits pivot pin 37 intov parallelposition along the second section 2S. A tension spring 54 is provided toassist the'movement of the bed frame 12into and `out of the sofa frame11, and another tension .spring V5 5 asf. sures that the leg 35 is inposition for supporting -the second section '25 in bed forming position.

The supporting leg 34 for the irst section 23 has a support member 56secured to its upper end and extending at right -angles thereto. Whenthe bed frame 412 (Figs. l and 2) is in bed forming position, vthesupport member 56 is substantially parallel with the first section 23. Alever 57 has one end pivoted to the support .member 56 by a pin 58 andits other end pivotally connected by a pin 59 to the third section 24.VWhen the iirst `section 23 is moved to a right angular position (Fig.3)'relative to the third section 24, the lever 57 causes the leg 34' andsupport'member 56 to pivot about the pin 36 so that the leg 34 isparallel to the first section 2,3 and the support member 56 extends atright angles or perpendicular thereto.

The movable upholstery'board 19 is supported by a rigid Yframe includingan angle piece 60 secured to arplate 61 'having pivotal connections withthe first section`23 and the lever 57. When the first section 23 isfolded relative to the third section 24, the portion of the Yiirstsection adjacent to its pivotal connection 27 moves into abutment withthe angle piece 60, as at 62 (Figs. 3 and 4). The upholstery board 19 isthus held in fixed spaced relation with the third section 24 in positionto be carried with the bed frame 12 into abutting coterminous positionwith the iXed upholstery board 18 of the sofa frame 11.

Ihe present invention is embodied in cooperable locking assemblies 64and 65 for locking the first and second sections 23 and 25 in xedsubstantially parallel seatforming relationship. It is well known thatwhen a mattress is folded into the bed frame of a Vsofa bed oonlstruction, it is compressed and therefore exerts an'up- Ward forcetending to move the upper or iirst section of the bed frame into anangular position relative tothe normal folded position that the firstsection should assume with respect to the second and third sections ofthe bed frame. Inasmuch as the seat cushions of 'the sofa are supportedon the rst section, it is necessary'to lock the `first section in xedfolded position relative to the second and third sections in order toprevent downward movement of the iirst section when `a person sits uponthe sofa seat.

The locking assembly 64 is provided to secure the first and secondsections 23 and 25 in fixed relationship. The locking assembly 64includes the support member 56, a seat plate 66 (Figs. 2 and 7) securedto the-second vsection 25 and a lever actuated latch member67. Referringto Figs. 4, 5 and 6, it will be seen that the free end 68y of thesupport member 56 is positioned on the seat plate 66 when the first andsecond sections 23 and 25 are in proper folded relationship. A pin orstud 69 (Figs. 3 and 7) Ais secured to the support member 56 adjacent toAthe free end 68. The latch member is pivoted to the plate 66 by a pin70 and has an arcuate margin 7.1 adapted to be moved over the stud 69 tohold the support member 56 seated on the plate 66. The `mechanism Vforpivoting the latch member 67 into and out of engagement with the stud 69includes a lever 72 pivotally connected to the 'latch member 67 bya pin73 and to the fourth section 26 "by a pin '74. A link 75 Yis pivotallyconnected 'to 'the lever 72 and to the end of the rarm 38 to assure theproper folding action of theV latch member 67.

When the frame sections 23, 24 and 25 have been folded into seat-formingrelation (Fig. 4) and the support 56 is seated on the plate 66, thelatch member 67 is in an unlocked position and remains so until the bedframe 12 is rocked into the sofaframe y11. Referring to Figs. 5 and 6.it will be seen that as the bed frame 12 is rocked into the sofa frame11, thesecond and fourth sections 25 and 26 fold about the pivot pin 29into an angular relation so that the lever 72 and link 75 cause thelatch member 67 to pivot into engagement with the stud 69. Accordingly,the first section 23 is locked in fixed spaced relation with the secondsection 25 to hold the mattress 13 in compressed `folded positiontherebetween. The angular pitch of the bed frame and mattress tends tocause the mattress to move section 23 away from section 2S. This 4iscaused also by the resiliency of the mattress especially with an innerspring construction.

The locking assembly 65 comprises gravity koperating means for vassuringthat the support 56 is substantially perpendicular to the first section23 so that vthe free end 68 Vof the support 56 will be in position tocontact 'the plate 66 and be locked thereon by the latch memberr67.

When the first and third sections 23 and 24 -are folded relative to thesecond section 25 and assume the position shown in Fig. 3, the naturalresiliency of the mattress V13 tends to unfold or move the iirst section23 out of perpendicular folded relationship with the third section 24 orcauses the rst section to tend to open up relative to the third sectionso that these Vsections define an obtuse angle. VIt is apparent from thedrawings Ythat the Yiirst and third sections, the support 56 and thelever 57 form a parallelograrn. Therefore, if the action of the mattresscauses the irst sectio'n 23 to unfold relative to the third .section 24,the support 56 will be pivoted into the same angular relation with thefirst section 23 as the third section .24. The angular relationshipwould cause the lowerend 68 of the support 56 to draw away from'or missthe seatplate 66 so that the stud 69 would not be contacted by the latchmember 67, whereby the first and second sections 23 and 2S would not belocked together. The angular relationship between the rst and thirdsections wouldalso cause the movable upholstery board 19 to bepositioned out of alignment with the xed upholstery `board 18, and thefree end of the first section 23 would be in a position to damage theback rest cushions (not shown) on the sofa frame V11. Accordingly, thelocking assembly 65 is provided 'to obviate `these problems by assuringthe proper folded relationship between the rst and third sections 23 and24 and the -support v56.

The locking assembly 65 comprises a pendent or gravity latch element 78having a latch pin engaging recess or marginal edge 79, the latchelement 78 being freely pivotally mounted on the supporting leg 34 by apin 80. A pin or stud 81 is secured to the lever 57 in position to beengaged by the edge 79 of the latch element 78 during the foldingmovement of the' iirst and third sections 23 and 24 -rrelative Vto thesecond section 25. This locking action takes place substantially at theposition shown in full lines in Fig. 3 and before the pressure exertedby the mattress 13 on the iirst section 23 can cause the objectionahleaction noted and move it out of perpendicular folded relation with thethird section 24.

It is now vapparent that a simplified Yeiiicient combination lockingarrangement has been provided for assuring the proper folding relationof the bed frame sectionsand maintaining them in fixed folded positionduring useof'the sofa bed as a sofa. Unfolding of the bed frame 12 vfromYthe sofa frame 11 operates in reverse of the folding-operation, thelatch member 67 being pivoted to unlocked 'position as the bed frame 12is rocked `up and out ofthe sofa frame and the gravity latch element 78pivoting to a disengaged Ycondition with the stud 81 as 'the first and Ythird sections 23 and 24 are unfolded relative to the second section 25.

It is now apparent that the present invention obviates the problems thathave arisen in the past with regard to maintaining the upper seatcushion supporting frame section of a foldable bed in fixed position sothat a mattress compressed between the folded frame sections will notmove it out of cushion supporting position. It is also obvious that thecooperation between the locking mechanisms 64 and 65 assure the properfolding and locking of the bed frame 12 within the sofa frame 11.

This invention is intended to cover all changes and modications of thepresent disclosure which will be readily apparent to one `skilled in theart, the present invention being limited only by the claims whichfollow.

What I claim is:

l. In combination with an articulated bed frame having first, second andthird relatively foldable sections adapted to move between an extendedbed deiining position and a folded seat forming relationship whereinsaid rst and second sections are substantially parallel and areinterconnected by said third section which is substantiallyperpendicular thereto; a support member pivotally attached at one end tosaid rst section and carrying rst stud means adjacent to the other end,a support seating member adapted to seat the other end of said supportmember when said first and second sections are in folded seat formingrelationship, a lever pivotally connected to said support member andsaid third section for moving the former to a substantiallyperpendicular position relative to said rst section, second stud meanssecured to said lever, gravity operating means for engaging said secondstud means to lock said lever in tixed position with said rst sectionand said support member and third section in perpendicular relationshipto said rst section, said gravity operating means engaging said secondstud means during folding movement of said first section toward foldedseat forming position with said second section, and lever actuated meansfor releasably engaging said rst stud means to secure said supportmember on said support seating member.

2. In combination with an articulated bed frame having rst, second andthird relatively foldable sections adapted to be moved into a seatsupporting position in a sofa frame; a leg pivotally connected to saidiirst section; a support member having one end secured in right angularrelation to said leg adjacent to the pivotal connection thereof, saidleg being prependicular to said first section when in bed formingposition and said support member being in substantially parallelrelation with said rst section; a lever connected between said supportmember and said third section for folding said support member into aposition substantially perpendicular to said first section andsubstantially parallel with said third section and for folding said leginto substantially parallel relation with said first section; a gravitylocking assembly including a stud member on said lever and a latchelement freely pivotally mounted on said leg in position to swing intolocking engagement with said stud during folding movement of said firstand third sections relative to said second section for maintaining saidsupport member substantially perpendicular to said first section; a seatplate mounted on said second section for seating the other end of saidsupport member when said rst and second sections are in folded seatsupporting position; another stud member secured to said support memberadjacent to the other end thereof; and lever actuated latch meansadapted to engage said other stud member upon folding movement of saidrst, second and third sections into said sofa frame whereby said supportmember is maintained in xed position extending between said rst andsecond sections.

3. In an articulated bed frame construction having rst and second framesections interconnnected by a third frame section and foldable from anextended position into substantially parallel relation with said thirdsection perpendicular thereto, and a leg pivotally mounted on said rstsection for supporting it in extended position and foldable by a leverconnected to the third section to a position along side of the firstsection when said bed frame is folded, and a mattress carried on saidbed frame and doubled on itself when said bed frame is folded; theimprovement which comprises gravity locking means including a stud onsaid lever, and a latch element freely swingably mounted on said leg andmovable into latching engagement with said stud as said bed frame isfolded, whereby spring-back of said mattress in folded condition isresisted and said rst and third sections are maintained in substantiallyperpendicular folded relationship.

4. In an articulated bed frame having rst and second frame sectionsinterconnected at one end by a third frame section and being foldableinto substantially parallel relation with said third frame sectionsubstantially perpendicular thereto, a mattress carried on said bedframe and doubled on itself in folded condition when said frame sectionsare folded, a frame supporting leg having a free end and a pivotalconnection with the other end of the first frame section and adapted tobe positioned adjacent to and substantially parallel with said rst framesection when it is in folded parallel relation with said second framesection, and a lever having one end pivoted to the third frame sectionand having its other end pivoted to said leg at a point spaced from thepivotal connection between the leg and the rst frame section on the sideof the pivotal connection toward the second frame section when saidfirst and second frame sections are in folded parallel relation wherebyrelative unfolding action between said rst and third frame sectionstoward straight-line position through an obtuse angular relationshipeffects movement of the free end of said leg away from said first andsecond frame sections toward a perpendicular position with the firstframe section; the improvement which comprises gravity locking meansbetween said leg intermediate its ends and said lever for releasablylocking said leg in substantially parallel position with said firstframe section to prevent the movement of said first frame section to anobtuse angular position relative to said third frame section underpressure of said mattress when said bed frame and mattress are in foldedcondition, said gravity locking means comprising a stud on said leverand a latch element freely pivoted on said leg and swingable intolatching engagement with said stud as said bed frame is folded.

References Cited in the tile of this patent UNITED, STATES PATENTS694,183 Olney Feb. 25, 1902 2,595,038 Woller Apr. 29, 1952 2,676,335Goodman Apr. 27, 1954 2,790,977 Bebry May 7, 1957 2,803,019 Fox Aug. 20,1957

